http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
냉난방용 배관 용접부의 전기화학적 부식특성에 관한 연구
임우조(Uh-Joh LIM),윤병두(Byoung-Du YUN),김환식(Hwan-Sik KIM) 한국수산해양교육학회 2007 水産海洋敎育硏究 Vol.19 No.1
This paper was studied on the electrochemical corrosion characteristics of weld zone for refrigerating and heating systems pipe. Austenitic stainless steel is widely applied to various fields of industry, because it is good to corrosion resistance and mechanical properties. But STS 304 is reliable to sensitization by heat cycle on welding. Therefore, in this study, electrochemical polarization test of STS 304 steel pipe manufactured by arc welding in tap water was carried out. And then polarization resistance behavior, uniform and local corrosion behaviors of base metal(BM), weld metal(WM) and heat affected zone(HAZ) for STS 304 pipe were investigated. The corrosion current density of STS 304 steel pipe is high in order of BM(153nA/cm2) < WM(614nA/cm2) < HAZ (1.675㎂/cm2). The pitting potential of HAZ(238mV/SCE) for STS 304 is lower than BM(1206mV/SCE) and WM(369mV/SCE). Therefore, the local corrosion like pitting corrosion, galvanic corrosion and crevice corrosion of HAZ for STS 304 is more sensitive than BM and WM.
임우조(Uh Joh Lim),윤병두(Byoung Du Yun) 한국유체기계학회 2000 유체기계 연구개발 발표회 논문집 Vol.- No.-
The crevice corrosion of local corrosion occur when the gap exist on metal surface. This crevice corrosion happen to region such as flange of pipe, contact part of casing, under gasket and packing, between valve disk and seat of pump etc. Especially The crevice corrosion of mild steel(SS 400) get serious.<br/> This paper was studied on the crevice corrosion of SS 400 in fluid environment. In 0%, 2%, 3.5%, 5% NaCl solution, the aspect of the crevice corrosion and polarization behavior under the crevice corrosion was investigated. And Weight loss rate of SS 400 with crevice and non-crevice was measured according to the NaCI concentration.<br/> The main results obtained are as follows :<br/> 1) Under crevice corrosion, the corrosion potential become less noble as the concentration of NaCl solution increased.<br/> 2) The current density under open circuit potential was high drained as concentration of NaCl solution increased by 3.5% but the concentration increased over 3.5%, the current density was low drained.<br/> 3) The weight loss rate of SS400 was increased as concentration of NaCl solution increased by 3.5%, but the concentration increased over 3.5%, that of SS400 was decreased.<br/> 4) Effect of oxygen for crevice corrosion in the concentration of 3.5% NaCl solution become sensitive than that of 0% NaCl solution.